Building Polyfills

Web Platform APIs for the Present and Future

A fieldbook for polyfill developers

Building Polyfills shares principles and guidelines for building polyfills that you can rely on. Author Brandon Satrom provides everything you need to build a traditional polyfill with a step-by-step walkthrough for constructing an HTML5 Forms Polyfill—a real-world, reasonably complex polyfill.

You’ll then explores an emerging trend on the web platform: the prollyfill, or "forward polyfill." This pattern—seen in libraries such as HitchJS, and the Polymer project—enables you to test and work with emerging concepts.

Sample Projects

The book features the development of two polyfills, one for the HTML5 Forms specification, and one for the experimental "Resource Priorities" draft spec. The repositories and source for both can be found below:

About the Author

Brandon Satrom is Director of Product Management for Telerik, the world's greatest developer tools company. An unabashed lover of the open web, Brandon loves to talk about HTML, JavaScript, CSS, open source and whatever new shiny tool or technology has distracted him from that other thing he was working on. Brandon has spoken at national, international and online events, and he loves hanging out with and learning from passionate designers and developers. Brandon lives in Austin, TX with his wife, Sarah, and three sons, Benjamin, Jack and Matthew.

Support or Contact

Having trouble with the sample projects, or have a question for the author? Follow Building Polyfills on Twitter, or you can contact Brandon directly with any questions or comments you may have..